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Since it is difficult for lateral stiffness of rope-guided rails to meet industry criteria in deep construction shaft, schematic diagrams of displacement suppression mechanisms (DSMs) are designed with a systematic approach demonstrated to reduce the lateral displacement of rope-guided rails in this paper. DSMs are simplified as planar four-bar and six-bar topological graphs based on topological theory. Each corresponding mechanical chain of these four-bar and six-bar mechanisms is divided into a rack, mechanical parts, prismatic, and revolute joints. An extended adjacency matrix is defined to represent the rack position, specific types of kinematic joints, and adjacency relationships between kinematic parts. Then, a symmetric vertex identification method is proposed with regard to planar 1-DOF (one degree of freedom) four-bar and six-bar topological graphs to get the sequences of prismatic joints for kinematic chains of DSMs. Finally, the alternative schematic diagrams of DSMs are obtained. The results show four-bar mechanisms with simple structure; few kinematical parts but less resident force are suitable for a mine shaft with small space and small swing. Six-bar mechanisms with two prismatic joints and three mechanical rack degree are applicable for wide shaft space in deep shaft, due to their stable structure and double resistant force. This development is helpful for DSM dimension synthesis design in future. [ABSTRACT FROM AUTHOR]

In this paper, dynamic characteristics of the symmetrical traction system with tensioned pulley acting on compensating rope is theoretically investigated. Due to the excitations from drum, the traction system will occur longitudinal and transverse vibration. In order to explore the differences between traditional traction system and tensioned traction system with different tensioned methods and seek the optimal method of vibration suppression, the damping cylinder and terminal tension acting on compensating rope between tensioned pulley and ground are placed. Caused by the change of the rope's property, the system will produce different dynamic responses. Here, the differential-algebraic equations (DAEs) are derived using Hamilton principle. The transverse and longitudinal nonlinear coupling of ropes are considered. The generalized- α method is selected to solve the DAEs. Based on the response characteristics of the system, the time-frequency characteristics with different terminal damping are obtained by CWT (continuous wavelet transform) and FFT (fast Fourier transform). From results, it can be seen that tensioned pulley plays an important role in suppressing transverse and longitudinal vibration of the symmetrical traction system compared with traditional traction system, especially by adding damping cylinder. The amplitude of system decreases exponentially with the increase of the terminal damping acting on tensioned pulley. Different running speeds of tensioned traction system are discussed. The results can inform the development of relevant mitigating strategies to minimize the effects of excessive vibrations. [ABSTRACT FROM AUTHOR]

The modeling and control of the multi-rope parallel suspension lifting system (MPSLS) are investigated in the presence of different and spatial distributed tensions; unknown boundary disturbances; and multiple constraints, including time varying geometric constraint, input saturation, and output constraint. To describe the system dynamics more accurately, the MPSLS is modelled by a set of partial differential equations and ordinary differential equations (PDEs-ODEs) with multiple constraints, which is a nonhomogeneous and coupled PDEs-ODEs, and makes its control more difficult. Adaptive boundary control is a recommended method for position regulation and vibration degradation of the MPSLS, where adaptation laws and a boundary disturbance observer are formulated to handle system uncertainties. The system stability is rigorously proved by using Lyapunov's direct method, and the position and vibration eventually diminish to a bounded neighborhood of origin. The original PDEs-ODEs are solved by finite difference method, and the multiple constraints problem is processed simultaneously. Finally, the performance of the proposed control is demonstrated by both the results of ADAMS simulation and numerical calculation. [ABSTRACT FROM AUTHOR]